Magnonic Bandgaps in Metalized 1-D YIG Magnonic Crystals

We investigate theoretically and experimentally magnonic bandgaps in a 1-D magnonic crystal consisting of a yttrium iron garnet film with periodically modulated thickness in contact with a metal. The theoretical model is based on the frequency-domain finite element method. The presented measurements of the transmitted spin-wave signal were performed with a vector network analyzer with coplanar and microstripe waveguide antennas for a magnonic crystal with and without metallic overlayer, respectively. The obtained results confirm that the presence of a metallic layer on top of the magnonic crystal shifts up the frequency of magnonic bandgaps.